Exercise machine



FIG. 1 is a perspective view of an exercise machine showing my new design;

FIG. 2 is a front view of the exercise machine shown in FIG. 1;

FIG. 3 is a rear view of the exercise machine shown in FIG. 1;

FIG. 4 is a left side view of the exercise machine shown in FIG. 1;

FIG. 5 is a right side view of the exercise machine shown in FIG. 1;

FIG. 6 is a top view of the exercise machine shown in FIG. 1; and,

FIG. 7 is a bottom view of the exercise machine shown in FIG. 1. 

The ornamental design for an exercise machine, as shown and described. 